Reland "Change ProxyResolver::GetProxyForURL() to take a unique_ptr<Request>* "

net/proxy/proxy_resolver_v8_tracing.h

Index: net/proxy/proxy_resolver_v8_tracing.h
diff --git a/net/proxy/proxy_resolver_v8_tracing.h b/net/proxy/proxy_resolver_v8_tracing.h
index cc329cd04f78b7c28930274a6f9010223c03a843..1dd1dbe2325fabfc7396a37f9f7884f3be819d7d 100644
--- a/net/proxy/proxy_resolver_v8_tracing.h
+++ b/net/proxy/proxy_resolver_v8_tracing.h
@@ -52,20 +52,13 @@ class NET_EXPORT ProxyResolverV8Tracing {
   // Gets a list of proxy servers to use for |url|. This request always
   // runs asynchronously and notifies the result by running |callback|. If the
   // result code is OK then the request was successful and |results| contains
-  // the proxy resolution information. If |request| is non-null, |*request| is
-  // written to, and can be passed to CancelRequest().
+  // the proxy resolution information.  Request can be cancelled by resetting
+  // |*request|.
   virtual void GetProxyForURL(const GURL& url,
                               ProxyInfo* results,
                               const CompletionCallback& callback,
-                              ProxyResolver::RequestHandle* request,
+                              std::unique_ptr<ProxyResolver::Request>* request,
                               std::unique_ptr<Bindings> bindings) = 0;
-
-  // Cancels |request|.
-  virtual void CancelRequest(ProxyResolver::RequestHandle request) = 0;
-
-  // Gets the LoadState for |request|.
-  virtual LoadState GetLoadState(
-      ProxyResolver::RequestHandle request) const = 0;
 };
 
 // A factory for ProxyResolverV8Tracing instances. The default implementation,